Author(s): L. Romano; A. Castorani; A. R. Di Santo; U. Fratino
Linked Author(s): Umberto Fratino
Keywords: No Keywords
Abstract: Several methods exist for extracting channel network from DEMs, even if, in the past, minor attention has been dedicated to the prediction of where channels begin. Understanding channel head location is essential for defining accurately the extent of channel network and it is important for geo-morphological and hydrologic analysis, transport and erosive processes, as well as for defining the landscape management issues. According to the scientific literature, channel heads are where the transition from diffusive to incisive erosive processes of hill-slope originates. This transition limit could be mathematically formulated by a parameter depending by a slope-dependent drainage area threshold. The purpose of this paper is to explore the possibility of defining channel network extent by using thresholds determined by a power law whose exponent characterizes universally the drainage basin geomorphology. For this aim, watershed descriptors could be used, such as drainage area-local slope relation and cumulative area distribution that can be easily derived from high resolution DEMs. The proposed methodology has been tested on streams located in Southern Italy, characterized by ephemeral regime but different morphological generation.
Year: 2010